WCl5 has attracted interest as CVD or ALD materials used to deposit W-containing films, such as W metal; WSi2; WX2, in which X is S, Se, or Te; W-doped amorphous Carbon, WO3, etc. (see, e.g., U.S. Pat. Nos. 9,595,470; 9,230,815, and 7,641,886 and US Pat App Pub Nos 2003/190424 and 2017/350013).
The crystal structure of WCl5 has been reported in Acta Crystallogr. (1978) B34, pp. 2833-2834. Its powder X-ray diffraction pattern was collected as International Centre for Diffraction Data Powder Diffraction File (PDF) card #04-005-4302. Okamoto reported the W-Cl phase diagram. Journal of Phase Equilibria and Diffusion, Vol. 31, No. 4 (2010).
WO2017/130745 to JX Nippon Mining & Metals Corp discloses a high purity tungsten pentachloride synthesis method.
WO2017/075172 to L'Air Liquide, Societe Anyonyme pour l'Etude et l'Exploitation des Procedes Georges Claudes discloses a vessel having internally wettable surface therein coated with one or more barrier layers to, for example, inhibit contamination of a material, such as a metal halide, contained in the vessel.
WCl5 suffers from being a solid, low vapor pressure precursor. Providing a sufficient flux to the processing chamber from a solid, low pressure precursor like WCl5 is difficult. Another challenge is to maintain a stable flux of precursor as the WCl5 containing package is being depleted. Both aspects are common to all solids, and may be addressed by using solid-specific packaging (see, e.g., US Pat App Pub Nos 2009/0181168 and 2017/0335450).
A need remains to supply a stable and reproducible flux of WCl5 vapors to a vapor deposition or etching process chamber over extended periods of time.